Re: [PATCH] x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task

From: Ingo Molnar
Date: Sat Aug 15 2020 - 17:58:15 EST



* Eric Dumazet <edumazet@xxxxxxxxxx> wrote:

> syzbot found its way in 86_fsgsbase_read_task() [1]
>
> Fix is to make sure ldt pointer is not NULL.

Thanks for this fix. Linus has picked it up (inclusive the typos to
the x86_fsgsbase_read_task() function name ;-), it's now upstream
under:

8ab49526b53d: ("x86/fsgsbase/64: Fix NULL deref in 86_fsgsbase_read_task")

By the fixes tag it looks like this should probably be backported all
the way back to ~v4.20 or so?

Thanks,

Ingo